Catalyzer arrangement for outboard motor

An outboard motor comprising an internal combustion engine having a first exhaust passage section, a housing unit adapted to be mounted on an associated watercraft, the housing unit having a second exhaust passage section, a support member mounted on the housing unit to support the engine above the housing unit, the support member defining third and fourth exhaust passage sections, the third exhaust passage section being wholly defined within the support member and communicating with the first exhaust passage section, the fourth exhaust passage section communicating with the second exhaust passage section, an exhaust unit detachably coupled with the support member and defining a fifth exhaust passage section communicating with the third and fourth exhaust passage sections, a space defined below a surface of the engine and above a surface of the support member, at least a portion of the fifth exhaust passage section extending through the space, and at least one catalyzer disposed in the fifth exhaust passage section of the exhaust unit.

An outboard motor comprising an internal combustion engine having a first exhaust passage section, a housing unit adapted to be mounted on an associated watercraft, the housing unit having a second exhaust passage section, a support member mounted on the housing unit to support the engine above the housing unit, the support member defining third and fourth exhaust passage sections, the third exhaust passage section being wholly defined within the support member and communicating with the first exhaust passage section, the fourth exhaust passage section communicating with the second exhaust passage section, an exhaust unit detachably coupled with the support member and defining a fifth exhaust passage section communicating with the third and fourth exhaust passage sections, a space defined below a surface of the engine and above a surface of the support member, the fifth exhaust passage section beyond the space, and at least one catalyzer disposed in the fifth exhaust passage section of the exhaust unit.

An outboard motor comprising an internal combustion engine having a first exhaust passage section, a housing unit adapted to be mounted on an associated watercraft, the housing unit having a second exhaust passage section, a support member mounted on the housing unit to support the engine above the housing unit, the support member defining third and fourth exhaust passage sections, the third exhaust passage section being wholly defined within the support member and communicating with the first exhaust passage section, the fourth exhaust passage section communicating with the second exhaust passage section, an exhaust unit detachably coupled with the support member and defining a fifth exhaust passage section communicating with the third and fourth exhaust passage sections, the fifth exhaust passage section, at least in part, having a diameter that is greater than either a diameter of the third exhaust passage section or a diameter of the fourth exhaust passage section, and at least one catalyzer disposed in the fifth exhaust passage section of the exhaust unit.

An outboard motor comprising a housing unit, an internal combustion engine disposed above the housing unit, the engine defining an internal exhaust passage, an exhaust guide member positioned between the housing unit and the engine to support the engine, the exhaust guide member defining first and second exhaust passages, the first exhaust passage communicating with the internal exhaust passage, the second exhaust passage communicating with an exhaust discharge passage defined within the housing unit, a generally C-shaped exhaust unit detachably affixed to the exhaust guide member, the exhaust unit being positioned generally rearward of the exhaust guide member, the exhaust unit defining another passage communicating with the first and second exhaust passages, the exhaust unit passage extending generally normal to an axis of an output shaft of the engine, and at least one catalyzer positioned within the exhaust unit passage.

An outboard motor comprising an internal combustion engine having a first exhaust passage section, a housing unit adapted to be mounted on an associated watercraft, the housing unit having a second exhaust passage section, a support member mounted on the housing unit to support the engine above the housing unit, the support member having third and fourth exhaust passage sections, the third exhaust passage section directly communicating with the first exhaust passage section without any intermediate passage, the fourth exhaust passage section communicating with the second exhaust passage section, an exhaust unit detachably coupled with the support member and defining a fifth exhaust passage section communicating with the third and fourth exhaust passage sections, the exhaust unit, at least in part, positioned generally rearward of the support member, and at least one catalyzer disposed in the fifth exhaust passage section of the exhaust unit.

An outboard motor comprising a housing unit, an internal combustion engine disposed above the housing unit, the engine having an output shaft that extends generally vertically, the engine defining an internal exhaust passage, an exhaust guide member positioned between the housing unit and the engine to support the engine, the exhaust guide member defining first and second exhaust passages, the first exhaust passage communicating with the internal exhaust passage, the second exhaust passage communicating with an exhaust discharge passage defined within the housing unit, an exhaust unit detachably affixed to the exhaust guide member, the exhaust unit being positioned generally rearward of the exhaust guide member, the exhaust unit defining a third exhaust passage communicating with the first and second exhaust passages, the third exhaust passage extending generally normal to an axis of the output shaft of the engine, a space is defined below a surface of the engine and above a surface of the exhaust guide member, and at least a portion of the third exhaust passage extending through the space, and at least one catalyzer positioned within the third exhaust passage.